Key blank



M. FALK KEY BLANK June E8, 31935..

Filed Jan. 2, 1954 Patented .le 18, i935 ,naar

hi T i accenti nar nnann Morris lFalk, lFitchbnrg, Mass.

Application `lannary 2,

3 Claims.

This invention relates to a special blank from which a finished key isto be made. l

The principal object of the invention is to provide a blank of suchconstruction that the cutting of the key Awill be reduced to itssimplest form. This is accomplished by producing a blank with notches inits edge between the points at which the cuts are to be made, leavingonly these points projecting so that the key is tted by cutting eachpoint separately to the proper depth.

Another object oithe invention is to provide a blank which can beinserted into the lock before it is cut, thus facilitating in someinstances the cutting of the key.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawingin which Fig. l is aface View of a key blank constructed in accordance with this invention;

Fig. 2 is an end view of the same, and Fig. 3 is a face view of a secondblank also constructed in accordance with this invention.

U to the large number" of stolen automobiles, pressure has been broughtto bear with lock manufacturers to design locks which would be morepick-proof and more resisting to theft. The usual alignment of disclocks in which the tumblers lock on one side and the key combination iscut on one side makes lock picking easy, as well as the reading ofcombinations because of the one-sided alignment. in order to get awayfrom this some manufacturers have adopted locks oi the same type withthe tumblers protruding on both sides of the cylinder. This renders thelock more pick-prooi and makes the combination more dimcult to read. I

However, the problem of servicing keys of this type has come about,inasmuch as this is a most dimcult type key to duplicate. .Thecombination, instead of being cut on one side in a straight line, mustbe cut on both sides of the blank, and any inaccuracy either in theblank or in the adjustment oi the machine will cause the duplicate keynot to operate the lock. The tumblers in locks of this type, and throughwhich the key is supposed to pass, are cut to a certain size muchsmaller than the actual width of the key itself. It is dimcult,therefore, for the locksmith to even try a blank key in the lock beforethe combination is cut, as the blank key will not enter the lock becausethe space between the tumblers is narrower the blank itself.

li have, therefore, designed a special key blank wherein some stock ofthe blank is already rerece, seriali ne. teaser (ci. tc-iic) moved, thusallowing the key to enter into the lock and pass through between thetumblers and leaving the full height of the blank on certain points,properly spaced, where the actual tumbler rests and where the actualcombination for said tumblers is to be cut. This type of blankeliminates about of the diiculty that locksmiths would have in trying tocut a key eitherI by code or duplication. All that is necessary for thelocksmith to do with this type of blank is to cut the proper combinationon the points only and the key is then ready to be used.

In the form of the invention shown in Figs. i. and 2 high portions orprojections it! are provided on each side which extend to the full Widthof the ordinary blank. Directly opposite each high portion l t is a sidenotch il providing clearance space to allow the inactive end of thetumbler to pass by it. This renders it possible to have a key madehaving its projections along opposite sides.

The way in which the key is cut is indicated by dotted lines. Eachprojection is merely cut off to a certain depth and the whole operationof cutting the key in this case would involve no more than the cuttingof these points.

Another feature of the blank as shown is that it is designed for a codehaving three cuts but in which the rst one is always cut away when theblank is-made. Therefore it is necessary to cut two depths only on eachside to bring the key into proper shape. Therefore, in this case, theiirst cut on each side is cut or left out of the key blank originally sothat no attention has to be paid to these cuts after the key blank ismade.

In the form shown in Fig. 3 the same principle is shown for a key inwhich the rst cut is not omitted. By supplying a code for the variousnumbers of .depths for each key it is very simple for a locksmith toduplicate or service these keys for his customers. He simply has to cuteach. projection in accordance With the code.

It will be noticed also' that on account of the wide clearance spaces itand their alternating with the opposite projections it is possible toinsert this key blank into the lock before it is cut. This in someinstances aids the locksmith in servicing the key.

Having thus described my invention andthe advantages thereof, I do notwish to be limited to the details herein disclosed, otherwise than asset forthin the claims, but what claim is:

` 1. A key blank for a tumbler lock having combination levers onopposite sides, the full width of said blank being greater than thespacebelock, whereby said projections can be cut individually to thedifferent depths required to t the key to the lock.

3. As an article of manufacture, a key blank having high projectionsalong its opposite edges with Wide clearance spaces between each twoadjacent projections, the projections on one edge alternating withprojections on the other so that the key blank will not at any point beof full Width, whereby it can be inserted fully into a 10 lock before itis cut.

MORRIS FALK.

